There are devices that require large current over 500-1000 amperes such as are welding device, an are cutting device or the like. Japanese Patent Application Laid-Open No. 2001-129667 discloses a power supply device that includes multiple switching converter circuits for performing AC (alternating current)/DC (direct current) conversion on commercial alternating current and that is capable of outputting large current to an arc welding device.
The operation of the switching converter circuits is controlled by a single controller, which enables formation of a single power supply device as a whole. The controller detects current output and collected from each of the switching converters and performs PWM control on each of the switching converter circuits such that the detected current matches target current.